2018/06/30 by Seung-Woo Lee, Jaewan Kim
Computer Science · Physics and Astronomy · #Coherent states #Cold Atom Physics and Bose-Einstein Condensates #Computer science #Interference (communication) #Phase (matter) #Photon #Photon antibunching #Physics #Quantum #Quantum Information and Cryptography #Quantum key distribution #Quantum mechanics #Quantum optics and atomic interactions #Statistical physics #quant-ph
paper · pdf · doi:10.1103/physreva.99.013847
published as Phys. Rev. A 99, 013847 (2019) · 8 pages, 5 figures, title and abstract changed, published version
openalex publication_date 2019/01/24 · arxiv created 2019/01/25 · arxiv updated 2019/01/28 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
We study a superposed weak coherent state that can fundamentally mimic an ideal single photon not only with respect to the number of photons but also in terms of an indeterminate phase. It is close to the single-photon state with high fidelity and exhibits fundamental features of single photons such as antibunching and Hong-Ou-Mandel interference. The emergence and vanishing of single-photon characteristics can be directly observed by changing two parameters, i.e., the mean photon number and number of phases. Our result shows that the uncertainty between the photon number and phase indeed constitutes the characteristics of single photons. Finally, we apply the superposed weak coherent state to quantum key distribution and demonstrate that it outperforms the typical approach using phase-randomized weak coherent states.